With the constant evolution of semiconductor technology, semiconductor dies are becoming increasingly smaller. More functions, however, need to be integrated into these semiconductor dies. Accordingly, these semiconductor dies have increasingly greater numbers of I/O pads, and the density of the I/O pads is quickly rising. As a result, the packaging of semiconductor dies is becoming more challenging.
Package technologies can be divided into multiple categories. In one of the categories, dies are sawed first, and then the “known-good-dies” are placed on a temporary wafer or panel-like carrier. Redistribution layers (RDLs) are made onto the “re-configured” wafer or panel after encapsulation or molding of the dies. Afterwards, conductive balls are attached, and then the “re-configured” wafer or panel is sawed to get a singulated package. The RDLs can “fan-out” the I/O pads to the area outside of the die area so as to accommodate high I/O devices for a given ball pitch requirement.
New packaging technologies have been developed to further improve the density and functions of semiconductor dies. These relatively new types of packaging technologies for semiconductor dies face manufacturing challenges, and they have not been entirely satisfactory in all respects.